In the past a number of different propeller guards have been proposed. Examples of these guards are shown in Kappas U.S. Pat. No. 4,070,984; Balius U.S. Pat. No. 4,078,516; Gruber U.S. Pat. No. 4,106,425 and Eller U.S. Pat. No. 4,680,017. Primary objectives of the inventions disclosed in the exemplified patents included the following:
"To provide a marine propulsion unit whose screw cannot accidentally touch a human body."
"To provide a propeller guard for an outboard motor or a stern drive unit constructed in a manner whereby the guard will substantially fully enclose the propeller . . . and thus render it nearly impossible for swimmers to come in contact with the propeller or the propeller to come in contact with the bottom or other submerged objects when running in shoal waters."
"To provide a propeller guard constructed in a manner whereby it may be readily removed from engagement with and installed on various forms of drive units."
"To provide a motorboat propeller guard which protects the propeller from damage . . . ."
In addition to the safety aspects of the use of a propeller guard, the protection of the propeller from damage is an important consideration. It is estimated that many boat owners who make frequent use of their boats will buy two or three propellers a year because of damage to unprotected propellers caused by floating logs and debris or by backing into rocks and pilings. Many of the available propeller guards are complicated structures and are subject to damage by the same causes. The cost of repairing or replacing the propeller guard may approach or exceed the cost of repairing or replacing a propeller.
It is an object of the present invention to provide a propeller guard that will meet the safety and performance objectives of known propeller guards while being constructed so as to be easily and inexpensively repairable if any damage occurs to the guard.
These and other objectives of the invention will be apparent from the following disclosure of a preferred embodiment thereof.